Vote: ↑ ↑ ↓ ↓ x (GroupID, 'Up'|'Down') */ public static function get_user_votes($UserID) { global $DB, $Cache; if ((int)$UserID == 0) { return array(); } $UserVotes = $Cache->get_value('voted_albums_'.$UserID); if ($UserVotes === false) { $DB->query('SELECT GroupID, Type FROM users_votes WHERE UserID='.$UserID); $UserVotes = $DB->to_array('GroupID', MYSQL_ASSOC, false); $Cache->cache_value('voted_albums_'.$UserID, $UserVotes); } return $UserVotes; } /** * Returns an array with torrent group vote data * @global CACHE $Cache * @global DB_MYSQL $DB * @param string|int $GroupID * @return array (Upvotes, Total Votes) */ public static function get_group_votes($GroupID) { global $DB, $Cache; $GroupVotes = $Cache->get_value('votes_'.$GroupID); if ($GroupVotes === false) { $DB->query("SELECT Ups AS Ups, Total AS Total FROM torrents_votes WHERE GroupID=$GroupID"); if ($DB->record_count() == 0) { $GroupVotes = array('Ups'=>0, 'Total'=>0); } else { $GroupVotes = $DB->next_record(MYSQLI_ASSOC, false); } $Cache->cache_value('votes_'.$GroupID, $GroupVotes, 259200); // 3 days } return $GroupVotes; } /** * Computes the inverse normal CDF of a p-value * @param float $GroupID * @return float Inverse Normal CDF */ private function inverse_ncdf($p) { /*************************************************************************** * inverse_ncdf.php * ------------------- * begin : Friday, January 16, 2004 * copyright : (C) 2004 Michael Nickerson * email : nickersonm@yahoo.com * ***************************************************************************/ //Inverse ncdf approximation by Peter John Acklam, implementation adapted to //PHP by Michael Nickerson, using Dr. Thomas Ziegler's C implementation as //a guide. http://home.online.no/~pjacklam/notes/invnorm/index.html //I have not checked the accuracy of this implementation. Be aware that PHP //will truncate the coeficcients to 14 digits. //You have permission to use and distribute this function freely for //whatever purpose you want, but please show common courtesy and give credit //where credit is due. //Input paramater is $p - probability - where 0 < p < 1. //Coefficients in rational approximations $a = array(1 => -3.969683028665376e+01, 2 => 2.209460984245205e+02, 3 => -2.759285104469687e+02, 4 => 1.383577518672690e+02, 5 => -3.066479806614716e+01, 6 => 2.506628277459239e+00); $b = array(1 => -5.447609879822406e+01, 2 => 1.615858368580409e+02, 3 => -1.556989798598866e+02, 4 => 6.680131188771972e+01, 5 => -1.328068155288572e+01); $c = array(1 => -7.784894002430293e-03, 2 => -3.223964580411365e-01, 3 => -2.400758277161838e+00, 4 => -2.549732539343734e+00, 5 => 4.374664141464968e+00, 6 => 2.938163982698783e+00); $d = array(1 => 7.784695709041462e-03, 2 => 3.224671290700398e-01, 3 => 2.445134137142996e+00, 4 => 3.754408661907416e+00); //Define break-points. $p_low = 0.02425; //Use lower region approx. below this $p_high = 1 - $p_low; //Use upper region approx. above this //Define/list variables (doesn't really need a definition) //$p (probability), $sigma (std. deviation), and $mu (mean) are user inputs $q = NULL; $x = NULL; $y = NULL; $r = NULL; //Rational approximation for lower region. if (0 < $p && $p < $p_low) { $q = sqrt(-2 * log($p)); $x = ((((($c[1] * $q + $c[2]) * $q + $c[3]) * $q + $c[4]) * $q + $c[5]) * $q + $c[6]) / (((($d[1] * $q + $d[2]) * $q + $d[3]) * $q + $d[4]) * $q + 1); } //Rational approximation for central region. elseif ($p_low <= $p && $p <= $p_high) { $q = $p - 0.5; $r = $q * $q; $x = ((((($a[1] * $r + $a[2]) * $r + $a[3]) * $r + $a[4]) * $r + $a[5]) * $r + $a[6]) * $q / ((((($b[1] * $r + $b[2]) * $r + $b[3]) * $r + $b[4]) * $r + $b[5]) * $r + 1); } //Rational approximation for upper region. elseif ($p_high < $p && $p < 1) { $q = sqrt(-2 * log(1 - $p)); $x = -((((($c[1] * $q + $c[2]) * $q + $c[3]) * $q + $c[4]) * $q + $c[5]) * $q + $c[6]) / (((($d[1] * $q + $d[2]) * $q + $d[3]) * $q + $d[4]) * $q + 1); } //If 0 < p < 1, return a null value else { $x = NULL; } return $x; //END inverse ncdf implementation. } /** * Implementation of the algorithm described at http://www.evanmiller.org/how-not-to-sort-by-average-rating.html * @param int $Ups Number of upvotes * @param int $Total Number of total votes * @return float Ranking score */ public static function binomial_score($Ups, $Total) { // Confidence level for binomial scoring (p-value .95) //define(Z_VAL, 1.645211440143815); // Confidence level for binomial scoring (p-value .90) define(Z_VAL, 1.281728756502709); if (($Total <= 0) || ($Ups < 0)) { return 0; } $phat = $Ups/$Total; return ($phat + Z_VAL*Z_VAL/(2*$Total) - Z_VAL*sqrt(($phat*(1-$phat)+Z_VAL*Z_VAL/(4*$Total))/$Total))/(1+Z_VAL*Z_VAL/$Total); } /** * Gets where this album ranks overall, for its year, and for its decade. This is really just a wrapper. * @param int $GroupID GroupID of the album * @param int $Year Year it was released * @return array ('overall'=>, 'year'=>, 'decade'=>) */ public static function get_ranking($GroupID, $Year) { $GroupID = (int)$GroupID; $Year = (int)$Year; if ($GroupID <= 0 || $Year <= 0) { return false; } return array('overall'=>Votes::get_rank_all($GroupID), 'year' =>Votes::get_rank_year($GroupID, $Year), 'decade' =>Votes::get_rank_decade($GroupID, $Year)); } /** * Gets where this album ranks overall. * @global CACHE $Cache * @global DB_MYSQL $DB * @param int $GroupID GroupID of the album * @return int Rank */ public static function get_rank_all($GroupID) { global $Cache, $DB; $GroupID = (int)$GroupID; if ($GroupID <= 0) { return false; } $Rankings = $Cache->get_value('voting_ranks_overall'); if ($Rankings === false) { $Rankings = array(); $i = 0; $DB->query("SELECT GroupID FROM torrents_votes ORDER BY Score DESC LIMIT 100"); while (list($GID) = $DB->next_record()) { $Rankings[$GID] = ++$i; } $Cache->cache_value('voting_ranks_overall', $Rankings, 259200); // 3 days } return isset($Rankings[$GroupID])?$Rankings[$GroupID]:false; } /** * Gets where this album ranks in its year. * @global CACHE $Cache * @global DB_MYSQL $DB * @param int $GroupID GroupID of the album * @param int $Year Year it was released * @return int Rank for its year */ public static function get_rank_year($GroupID, $Year) { global $Cache, $DB; $GroupID = (int)$GroupID; $Year = (int)$Year; if ($GroupID <= 0 || $Year <= 0) { return false; } $Rankings = $Cache->get_value('voting_ranks_year_'.$Year); if ($Rankings === false) { $Rankings = array(); $i = 0; $DB->query("SELECT GroupID FROM torrents_votes AS v JOIN torrents_group AS g ON g.ID = v.GroupID WHERE g.Year = $Year ORDER BY Score DESC LIMIT 100"); while (list($GID) = $DB->next_record()) { $Rankings[$GID] = ++$i; } $Cache->cache_value('voting_ranks_year_'.$Year , $Rankings, 259200); // 3 days } return isset($Rankings[$GroupID])?$Rankings[$GroupID]:false; } /** * Gets where this album ranks in its decade. * @global CACHE $Cache * @global DB_MYSQL $DB * @param int $GroupID GroupID of the album * @param int $Year Year it was released * @return int Rank for its year */ public static function get_rank_decade($GroupID, $Year) { global $Cache, $DB; $GroupID = (int)$GroupID; $Year = (int)$Year; $Year = (int)$Year; if ((int)$GroupID <= 0 || (int)$Year <= 0) { return false; } // First year of the decade $Year = $Year - ($Year % 10); $Rankings = $Cache->get_value('voting_ranks_decade_'.$Year); if ($Rankings === false) { $Rankings = array(); $i = 0; $DB->query("SELECT GroupID FROM torrents_votes AS v JOIN torrents_group AS g ON g.ID = v.GroupID WHERE g.Year BETWEEN $Year AND ".($Year+9)." AND g.CategoryID = 1 ORDER BY Score DESC LIMIT 100"); while (list($GID) = $DB->next_record()) { $Rankings[$GID] = ++$i; } $Cache->cache_value('voting_ranks_decade_'.$Year , $Rankings, 259200); // 3 days } return isset($Rankings[$GroupID])?$Rankings[$GroupID]:false; } } ?>